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This paper investigates article use in learner corpora in order to (i) examine how both the native language and proficiency level influence the patterns of article use, misuse, and omission and (ii) examine whether patterns of the overuse of the with specific indefinites found in experimental studies are also present in learner corpora. To this end, 200 texts from the Cambridge Learner Corpus are examined: 100 texts from Spanish-speaking learners of English and 100 texts from Russian and Ukrainian-speaking learners of English. Each subcorpus has an even distribution between learners at CEFR B1 and B2 proficiency levels. The results confirm that the learners’ native language affects article use: speakers of Spanish, an article language, show an increase in correct article use with proficiency; in contrast, speakers of Russian, an article-less language, continue to make article errors. On the other hand, the particular patterns of article misuse found in prior experimental work are not found in learner corpora: while Russian-speaking learners do overuse the with indefinites in the corpora, this error type is not tied to specificity. This null finding could be due in part to the relatively low number of errors of the overuse in the learner corpus.
The test-negative design (TND) has become a standard approach for vaccine effectiveness (VE) studies. However, previous studies suggested that it may be more vulnerable than other designs to misclassification of disease outcome caused by imperfect diagnostic tests. This could be a particular limitation in VE studies where simple tests (e.g. rapid influenza diagnostic tests) are used for logistical convenience. To address this issue, we derived a mathematical representation of the TND with imperfect tests, then developed a bias correction framework for possible misclassification. TND studies usually include multiple covariates other than vaccine history to adjust for potential confounders; our methods can also address multivariate analyses and be easily coupled with existing estimation tools. We validated the performance of these methods using simulations of common scenarios for vaccine efficacy and were able to obtain unbiased estimates in a variety of parameter settings.
Light gradients are an inherent feature in aquatic ecosystems and play a key role in shaping the biology of phytoplankton. Parasitism by chytrid fungi is gaining increasing attention as a major control agent of phytoplankton due to its previously overlooked ubiquity, and profound ecological and evolutionary consequences. Despite this interest, if and how light conditions modulate phytoplankton chytridiomycosis remains poorly studied. We investigated life-history traits of a chytrid parasite, Rhizophydium megarrhizum, under different light intensities and spectral compositions when infecting two closely related planktonic cyanobacteria with different light-harvesting strategies: Planktothrix rubescens and P. agardhii. In general, parasite transmission was highest under light conditions (both intensity and quality) that maximized growth rates for uninfected cyanobacteria. Chytrid encystment on hosts was significantly affected by light intensity and host strain identity. This likely resulted from higher irradiances stimulating the increased discharge of photosynthetic by-products, which drive parasite chemotaxis, and from strain-specific differences at the cell-surface. Comparisons of parasite transmission and host growth rates under different light conditions suggest the potential for epidemic development at higher irradiances, whereas host and parasite could coexist without epidemic outbreaks at lower light levels. These results illustrate the close relationship between parasite transmission and host fitness, which is ultimately modulated by the external environment.
This commentary discusses the value of considering general interpersonal mechanisms across personality disorders, argues that specific strategies for addressing personality disorder problems may lie in the specifics of different relationship contexts, and notes the importance of developing a model of how psychotherapy targets relationship contexts so as to improve psychological health.
Social phobia (SP) has onset during early adolescence, and is associated with significant impairment in social and educational functioning of adolescents. Therefore, valid and easy-to-use tools for screening and identification of SP among adolescent community populations are needed. We investigated both construct and discriminative validity, and screening properties of the 17-item Social Phobia Inventory (SPIN) relative to SP diagnoses based on a semi-structured clinical interview (K-SADS-PL), in a sample of 752 12 to 17-year-old Finnish students from general population. The SPIN demonstrated good properties to differentiate adolescents with SP and those with sub-clinical SP symptoms (SSP), from adolescents without SP. The SPIN also differentiated adolescents with SP from those with depressive and disruptive disorders. In this sample 27% of participants scored above the previously suggested SPIN cut-off (15 points) for adolescent SP. We suggest using a somewhat higher cut-off score, 24 points, when using the SPIN as a screen for SP in general adolescent populations. This cut-off score resulted in a sensitivity of 81.2%, a specificity of 85.1%, a positive predictive value of 26.9%, and a negative predictive value of 98.6% in relation to the SP diagnosis in our sample. To screen for both SP and SSP, 19 points as a cut-off score produced satisfactory diagnostic efficiency statistics. The SPIN appears to have good properties for screening and identification of adolescent SP.
Chapter 5 deals with (asymmetric) differential object marking (DOM), a phenomenon occurring in over 300 languages whereby the object of a verb can be either marked or unmarked for morphological case, depending on a number of factors. These factors have to do with the individuation/prominence of the object, often its definiteness, specificity and animacy value. The chapter begins with illustrations of the phenomenon in several languages, showing its sensitivity to different properties of the object. The reasoning behind DOM is then discussed. Two specific proposals are considered: one treats DOM as a signal of higher transitivity; the other views it as a disambiguation mechanism whereby a non-prototypical object is marked and, as a result, not confused with the subject. In addition to features of the object, properties of the verb have been argued to play a role in DOM; this relation is considered in a separate section. Further, several cross-linguistic analyses of the phenomenon are reviewed.
Chapter 6 is dedicated to the non-canonical genitive case-marking on objects in Balto-Slavic languages, concentrating primarily on Russian facts. It deals with the genitive/accusative alternation on direct objects and, to a lesser degree, the genitive/nominative alternation on subjects. First, Genitive of Negation and Intensional Genitive are discussed. The two phenomena, which involve genitive case-assignment to the object of a negated or intensional verb, are unified under the term Irrealis Genitive. The chapter considers those properties that affect the choice of case, including definiteness, scope, number, abstractness, and a range of syntactic and semantic analyses that have been proposed to account for the case alternations. Second, we take a look at Partitive Genitive. Here, the genitive object is interpreted quantificationally, indicating an indeterminate amount of the matter denoted by the noun. Characteristics of the phenomenon, such as homogeneity of the object and perfectivity of the verb, are listed, and two accounts are considered: one positing that the non-canonical genitive is assigned by a phonologically empty quantifier and the other treating genitive objects as nominal measure predicates. The chapter also discusses the relation between non-canonical genitive case and DOM.
The phenomenon of case has long been a central topic of study in linguistics. While the majority of the literature so far has been on the syntax of case, semantics also has a crucial role to play in how case operates. This book investigates the relationship between semantics and case-marking in the languages of the world, exploring a range of phenomena in which case-assignment is affected by (or affects) meaning. By bringing together data from a wide range of languages, representing different language families, a cross-linguistic picture emerges of the correlation between case and meaning. Different approaches to the phenomena are considered, including both syntactic and semantic analyses, and the question is raised as to whether case can be treated as meaningful, ultimately helping us shed light on the broader connections between grammar and meaning and, moreover, grammar and the human cognition.
To compare the sensitivity, specificity, and predictive value of published versus sample-based norms to detect early dementia in the Uniform Data Set (UDS).
Methods:
The UDS was administered to 526 nondemented participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Baseline scores were standardized using published norms and healthy control data from ADNI corrected for age, education, and sex. Subjects obtaining two scores < −1 SD (determined separately using published and sample norms) were labeled “at risk for dementia.” Both methods were compared on sensitivity, specificity, and positive/negative predictive value (PPV/NPV) for dementia at follow-up.
Results:
Risk scores derived from published data had 86.1% sensitivity, 62.0% specificity, 68.6% accuracy, 46.1% PPV, and 92.2% NPV. Those from sample norms were more sensitive (91.0%), less specific (52.9%), and less accurate (63.3%), with worse PPV (42.1%) and similar NPV (94.0%). Sample norms were better at identifying incident dementia cases with relatively lower education than those with higher education. Discrepancies between both methods were more common in women.
Conclusions:
Sample norms are marginally more sensitive than published norms for predicting dementia, while published norms are slightly more accurate. Accuracy of risk estimates for women and those with lower education may be increased using locally generated norms.
Philosophers through the ages have stressed time as a critical variable in life, and developmentalists today pretend to a lifespan framework. Paradoxically, many construals of time are still neglected in developmental science. This chapter focuses on time and fleshes out three developmental perspectives on time: the chronosystem from the bioecological systems framework, transaction, and specificity.
Bioecological systems theory characterizes development as a joint function of process, person, context, and time. The principle of transaction in development asserts that characteristics of individuals shape their experiences, and reciprocally experiences shape the characteristics of individuals, through time. Finally, the specificity principle contends that understanding lifespan development depends critically on what is studied in whom, how, and when. Time fits integrally into each prevailing developmental perspective.
Philosophers through the ages have stressed time as a critical variable in life, and developmentalists today pretend to a lifespan framework. Paradoxically, many construals of time are still neglected in developmental science. This chapter focuses on time and fleshes out three developmental perspectives on time: the chronosystem from the bioecological systems framework, transaction, and specificity.
Bioecological systems theory characterizes development as a joint function of process, person, context, and time. The principle of transaction in development asserts that characteristics of individuals shape their experiences, and reciprocally experiences shape the characteristics of individuals, through time. Finally, the specificity principle contends that understanding lifespan development depends critically on what is studied in whom, how, and when. Time fits integrally into each prevailing developmental perspective.
Barteria fistulosa and B. dewevrei, central African rain-forest trees, provide nesting cavities for Tetraponera aethiops and T. latifrons ants, respectively, which protect them against herbivores. To compare protection efficiency between these two symbioses, for 20 plants of each species in two sites in Gabon we measured the time elapsed before ants reached a focal leaf, for host leaves that were undisturbed, damaged (cut with scissors) or subjected to slight vibration (mimicking such damage), and for damaged leaves of the non-host Barteria species. Tetraponera aethiops displayed stronger protective behaviour than did T. latifrons. Time to reach a damaged host leaf (4.5 ± 2.6 min, mean ± SD) did not differ significantly from time to reach a leaf subjected to slight vibration (5.2 ± 3.0 min) for T. aethiops, but response to a leaf subjected to slight vibration (9.5 ± 1.9 min) was significantly slower than that to a damaged leaf (7.8 ± 1.9 min) for T. latifrons. The faster response of T. aethiops to slight vibration may have masked a response of this species to chemical signalling. Both ants reached damaged host leaves faster than damaged leaves of the non-host Barteria sp., indicating host plant specificity in ant responses.
Vascular surgery patients are nutritionally vulnerable. Various malnutrition screening and assessment tools are available; however, none has been developed or validated in vascular patients. The present study aimed to: (1) investigate the validity of four commonly administered malnutrition screening tools (Malnutrition Screening Tool (MST), Malnutrition Universal Screening Tool (MUST), Nutrition Risk Screen-2002 (NRS-2002) and the Mini-Nutritional Assessment – Short Form (MNA-SF) and an assessment tool (the Patient-Generated Subjective Global Assessment (PG-SGA)) compared against a comprehensive dietitian’s assessment and (2) evaluate the ability of the instruments to predict outcomes. Vascular inpatients were screened using the four malnutrition screening tools and assessed using the PG-SGA. Each was assessed by a dietitian incorporating nutritional biochemistry, anthropometry and changes in dietary intake. Diagnostic accuracy, consistency and predictive ability were determined. A total of 322 (69·3 % male) patients participated, with 75 % having at least one parameter indicating nutritional deficits. No instrument achieved the a priori levels for sensitivity (14·9–52·5 %). Neither tool predicted EuroQoL 5-dimension 5-level score. All tools except the MNA-SF were associated with length of stay (LOS); however, the direction varied with increased risk of malnutrition on the MUST and NRS-2002 being associated with shorter LOS (P=0·029 and 0·045) and the reverse with the MST and PG-SGA (P=0·005 and <0·001). The NRS-2002 was associated with increased risk of complications (P=0·039). The MST, NRS-2002 and PG-SGA were predictive of discharge to an institution (P=0·004, 0·005 and 0·003). The tools studied were unable to identify the high prevalence of undernutrition; hence, vascular disease-specific screening and/or assessment tools are warranted.
The performance of a new point-of-care diagnostic (Mastatest), an on-farm test designed to identify bacteria and provide antibiotic sensitivity testing information from milk samples, was compared with standard microbiological culture methods. A total of 292 milk samples from clinical mastitis cases in dairy cows on New Zealand dairy farms were examined, and latent class analysis was used to estimate the performance characteristics of both tests. Two hundred and fifty-six samples (87.7%) demonstrated bacterial infection in standard culture, and 269 (92.1%) using the point-of-care diagnostic. The most common bacterial species detected was Streptococcus uberis, found in 195 samples (66.8%) using standard culture and 190 samples (65.1%) using the point-of-care diagnostic. Latent class analysis found no significant differences in test characteristics between the point-of-care diagnostic and standard culture. The estimated sensitivity and specificity of the point-of-care diagnostic against all targets combined were 94.6 and 72.1% respectively; the corresponding estimates for standard culture were 90.5 and 73.9%. Comparison of antibiotic susceptibility testing using the point-of-care diagnostic and the reference method showed similar trends and, in some cases, identical MIC50 and MIC90 values, with at most one antibiotic dilution difference.
Understanding how individual parasite traits contribute to overall fitness, and how they are modulated by both external and host environment, is crucial for predicting disease outcome. Fungal (chytrid) parasites of phytoplankton are important yet poorly studied pathogens with the potential to modulate the abundance and composition of phytoplankton communities and to drive their evolution. Here, we studied life-history traits of a chytrid parasite infecting the planktonic, bloom-forming cyanobacterium Planktothrix spp. under host genotype and thermal variation. When expressing parasite fitness in terms of transmission success, disease outcome was largely modulated by temperature alone. Yet, a closer examination of individual parasite traits linked to different infection phases, such as (i) the establishment of the infection (i.e. intensity of infection) and (ii) the exploitation of host resources (i.e. size of reproductive structures and propagules), revealed differential host genotype and temperature × host genotype modulation, respectively. This illustrates how parasite fitness results from the interplay of individual parasite traits that are differentially controlled by host and external environment, and stresses the importance of combining multiple traits to gain insights into underlying infection mechanisms.
The Bipolar Spectrum Diagnostic Scale (BSDS) is widely validated and used as a screening tool for bipolar disorder. However, there is no BSDS validated version for its use in Mexican population. The aim of the present study was to examine the BSDS diagnostic capacity, and to evaluate its criterion validity and internal consistency for its use in Mexican psychiatric patients. We recruited 200 patients who attended the psychiatric outpatient service of a Mental Health Specialized Hospital and were screened for bipolar disorder using BSDS. To determine the cut-off point, sensitivity and specificity, we used the SCID–I diagnosis as the gold standard in 100 participants with bipolar disorder and 100 with major depression. Internal consistency according to Cronbach’s coefficient alpha was .81. The area under ROC curve for the overall discriminability of BSDS against the criterion of SCID–I for bipolar disorder was .90. Finally, a cut-off value of 12 reached the most stable sensitivity and specificity, with predictive powers higher than .80. In conclusion, the properties of the scale including internal consistency, sensitivity and specificity, make of BSDS a valuable instrument for screening bipolar disorder in Mexican psychiatric population.
Colposcopes are expensive, heavy, and need specialized technical service, which may outreach the capacity of low-resource settings. Our aim was to assess the performance of smartphone-based digital images for the detection of cervical intraepithelial neoplasia grade 2 or worse (CIN2+).
Methods:
Human papillomavirus (HPV)-positive women recruited through a cervical cancer screening campaign had VIA/VILI assessment (visual inspection after application of acetic acid/lugol's iodine). Cervical digital images were captured with a smartphone camera, randomly coded with no prior selection and distributed on an online database (Google Forms) for evaluation. Healthcare providers were invited to evaluate the images and identify CIN2+. The gold standard was the histopathological diagnosis. The sensitivity and specificity for the detection of CIN2+ was assessed for each reader and reported with the 95 percent confidence interval (Clopper-Pearson method).
Results:
One hundred twenty-five consecutive HPV-positive women were included, with 19 CIN2+ (15.2 percent). Forty-five gynecologists completed the assessment, one-third were considered as experts (>50 colposcopies) and two-thirds as novices (<50 colposcopies). The sensitivity and specificity for CIN 2+ detection was 71.3 percent (67.0–75.7 percent) and 62.4 percent (57.5–67.4 percent), respectively. The performance of novices and experts was similar. The readers assessed 73.1 percent of images as acceptable for diagnostic.
Conclusion:
Smartphone-based digital images, with its high portability, have a great potential for the diagnosis of CIN2+ in low-resource context.
Spirometry is known to be a gold standard for the diagnosis of chronic obstructive pulmonary disease (COPD). COPD Assessment Test (CAT) is an eight-item questionnaire currently in use to evaluate patients with COPD. In the present study, we aimed to evaluate if CAT is an adequate tool for screening COPD.
Methods
In total, 600 persons aging ⩾40 years old were randomly selected from three different family practice units located in the city center. CAT was asked to the participants and a spirometry was used to assess pulmonary obstruction. Pulmonary obstruction was defined as forced expiratory volume in first second/forced vital capacity (FEV1/FVC)<70% and then COPD diagnosis was confirmed with the reversibility test. The relationship between CAT results and pulmonary function test values was evaluated.
Results
In this sampling, the prevalence of COPD was 4.2%. Reliability of the CAT in the study group was acceptable (Cronbach’s α: 0.84). The CAT scores was significantly higher in patients with COPD (P<0.001). There was a significant negative correlation between CAT score and FEV1, FVC and FEV1/FVC ratio (r=−0.31, P<0.001; r=−0.26, P<0.001; r=0.18, P=0.001). Among smokers, phlegm was the predominating symptom (P=0.01). Sensitivity of CAT was 66.67% and its specificity was 75.15% to determine COPD.
Conclusions
CAT is a reliable questionnaire and there is an apparent relationship between the total CAT scores and COPD. However, CAT’s ability to screen COPD is limited since it may miss the symptom-free cases.